/*背景图*/

.a_background {
    width: 100%;
    height: 100%;
    position: absolute;
}

.a_background_top{
    width: 100%;
    height: 71.6%;
    background-image: url("pic/a_bg_top.png");
    background-size: 100% 100%;
}


.a_background_middle{
    width: 100%;
    height: 13.1%;
    background-image: url("pic/a_bg_middle.png");
    background-size: 100% 100%;
}

.a_background_botton{
    width: 100%;
    height: 15.3%;
    background-image: url("pic/a_bg_botton.png");
    background-size: 100% 100%;
}
/*-------- 太阳自转以及动画 --------*/
#sun {
    background: url("pic/sun.png") no-repeat;
    position: absolute;
    z-index: 1;
    top: -30px;
    height: 201px;
    width: 201px;
    right: 40%;
}

.rotation {
    -webkit-animation-name: rotation;
    -webkit-animation-duration: 30s;
    -moz-animation-name: rotation;
    -moz-animation-duration: 30s;
}

@-webkit-keyframes rotation {
    0%{
        transform: translateX(0) translateY(0);
    }
    100%{
        transform: translateX(-2000px) translateY(400px);
    }
}

@-moz-keyframes rotation {
    0%{
        transform: translateX(0) translateY(0);
    }
    100%{
        transform: translateX(-2000px) translateY(400px);
    }
}
/* 天空云 */       
.cloud {
    z-index: 2;
    position: absolute;
}

.cloud1 {
    width: 181px;
    height: 101px;
    left: -5%;
    top: 15%;
    background: url("pic/cloud1.png");
}


.cloud2 {
    width: 301px;
    height: 140px;
    right: -5%;
    background: url("pic/cloud2.png");
}

.cloud1Anim{
    -webkit-animation-name: smallCloud;
    -webkit-animation-duration: 30s;
    -webkit-animation-iteration: infinite;
    -moz-animation-name: smallCloud;
    -moz-animation-duration: 30s;
    -moz-animation-iteration: infinite;
}

.cloud2Anim{
    -webkit-animation-name: largeCloud;
    -webkit-animation-duration: 60s;
    -webkit-animation-iteration: infinite;
    -moz-animation-name: largeCloud;
    -moz-animation-duration: 60s;
    -moz-animation-iteration: infinite;
}


@-webkit-keyframes smallCloud {
    0% {
        left: -5%;
    }
    100% {
        left: 100%;
    }
}

@-moz-keyframes smallCloud {
    0% {
        left: -5%;
    }
    100% {
        left: 100%;
    }
}

@-webkit-keyframes largeCloud {
    0% {
        right: -5%;
    }
    100% {
        right: 100%;
    }
}

@-moz-keyframes largeCloud {
    0% {
        right: -5%;
    }
    100% {
        right: 100%;
    }
}